Unlimited mass can have not gravity

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Discussion Overview

The discussion centers on the theoretical possibility of an object with unlimited mass not exhibiting gravity. Participants explore concepts related to mass, gravity, and black holes, questioning the implications of infinite mass within the framework of relativity and cosmology.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • Some participants argue that infinite mass is theoretically impossible according to the laws of relativity, suggesting that discussions about it may be irrelevant.
  • Others propose that black holes, while having large but finite mass, demonstrate significant gravitational effects, challenging the notion of infinite mass.
  • A participant notes that black holes are often described as having infinite gravitational force at their singularities, but clarifies that this does not equate to having infinite mass.
  • Another participant mentions that the total amount of mass-energy in the visible universe is finite, which implies that infinite mass cannot exist.
  • One contribution discusses the concept of limits in physics, suggesting that while infinite mass is not possible, one can approach it in theoretical equations.
  • There is a clarification regarding the invariance of mass in the standard model, indicating that mass does not exhibit relativity in the same way as other quantities.

Areas of Agreement / Disagreement

Participants generally agree that infinite mass is not possible, but there are competing views regarding the implications of this on gravitational theory and the nature of black holes. The discussion remains unresolved regarding the broader theoretical implications of infinite mass.

Contextual Notes

Limitations include the dependence on definitions of mass and gravity, as well as the unresolved nature of certain mathematical concepts related to limits and theoretical frameworks.

Jarritos
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Me and a friend where talking and he was saying that something that has unlimited mass can have not gravity. This notion goes against pretty much everything I was taught in school. So my questions is this theoretically possible?
 
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nothing can earn the mass of infinity according to the law of relativity so it is not theoretically possible to prove this
 


(I know next to no cosmology, please fill me in on my mistakes) Well, the nearest real concept that I can think of to an infinite mass object is a black hole, i.e. finite mass at a singularity, which clearly has gravity. We're orbiting a big fat one(s) right now.
 


A black hole does not have infinite mass at the singularity, it sometimes is said to have an infinite force of gravity at the singularity. Those are two very different things. Also if you throw something into a black hole from a safe distance you will never see it actually go into the black hole. The light that it reflects will be red shifted from here to eternity and if you have a sensitive enough device it will always "see" the object falling into the black hole.
 


Black holes do not have infinite mass.
 


neu said:
a black hole, i.e. finite mass at a singularity, which clearly has gravity. We're orbiting a big fat one(s) right now.

Notice the word finite before mass in my post. You both apear to think I said infinite, I did not.

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I would agree that "infinite mass' is theoretically impossible, thus any considerations about it might be considered essentially irrelevant.
But that's only a point-of-view, and I could be wrong.
 


The BH at our galaxy center is known to have 4 million times mass of the sun, and some BHs have billion times of sun, so their mass is huge though not infinity.
 


It is not possible to have infinite mass, but you can write a limit:

{Lim}_{M\rightarrow\infty}{G}\frac{{M}\cdot{m}}{R^{2}}=\verb!a s#&@ ton of gravity!
 
  • #10


Kurdt said:
Black holes do not have infinite mass.
not only the black holes but actually nothing have infinite mass according to the laws of relativity of mass
 
  • #11


I don't know any reason infinite mass is ruled out in theory, but thanks to modern cosmology we know that the total amount of mass-energy in the visible universe is finite.

not only the black holes but actually nothing have infinite mass according to the laws of relativity of mass

In the standard model mass is a lorentz invariant scalar quantity, so there is no 'relativity of mass' i.e. mass is invariant under the actions of the lorentz group.

In physics units \hbar = c = 1 there is only one kind of dimensionful quantity, energy (which has the same units as mass) or the reciprocal of energy which is distance (which has the same units as time). In other words, since mass has units we can always choose the system of units so that the masses that appear in our equations are arbitrarily large numbers, and the laws of physics are unaffected by a chang of units.

When we solve the planetary orbit or the hydrogen atom, we use the reduced mass approximation with the sun/proton being infinitely heavy compared to th planet/electron.
 
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